1. Field
The present disclosure relates to a cathode active material, a cathode and a lithium secondary battery including the cathode active material, and a method of preparing the cathode active material.
2. Description of the Related Art
Lithium secondary batteries have been used as a power source for many portable devices due to their high energy density and ease of design.
Lithium transition metal oxides, such as LiCoO2, LiNiO2, LiMn2O4, or LiFePO4 have been used as cathode active materials in lithium secondary batteries.
For example, layered LiCoO2 has a reversible capacity of about 200 milliampere-hours per gram (mAh/g) or less, and has reached the limit of increases in the energy density and the power characteristics thereof. LiNiO2, which is also layered, has a larger discharge capacity, but the cycle characteristics thereof are not as good as LiCoO2. Furthermore, when LiNiO2 is used to provide a high energy density battery, the battery may be structurally unstable and prone to failure in the event of structural deformation in a charged state.
Thus the remains a need for a cathode active material having improved structural stability and having improved initial discharge capacity, lifespan characteristics, and voltage stability, in particular for high energy density applications.